I'm really torn between 4 and 5 stars.
This was a terrifying book. Terrifying in the most primal way. The fear it builds does not come from a wicked beast or something paranormal, it comes from something that's all to real and can't be fought: a virus inside you.
The writing style really felt like a Stephen King book, with its background character development and interviews and case file parts (which was on purpose, as the author acknowledges). That said I really loved it.
The transition from innocent childhood where the adults handle everything, to the sad truth that adults are sometimes as lost as children, was really well done. Every kid had its own fleshed out character and took a reasonable part in the story.
The gory and disgusting “action” parts were evenly spaced out and believable.
But it's also a sad book. There's nothing good happening to any of the characters. All they got left are memories of better times, on which they cling on while going through hell. It doesn't have a happy ending, which I really like. Life isn't like the fairy tales.
So why not 5 stars? Because all the animal cruelty left a bitter taste in my mouth. I know that it WAS there to do just that, and for a few characters those scenes were crucial, but it was a bit too fleshed out for my tastes. Like the author really had fun writing sites full of those stuff.
Yes yes, I know that drawing the line on animal cruelty in a book where kids slaughter themselves is weird, but that's just how I roll. I can't help it.